The Supreme Personality of Godhead is the best friend and well-wisher of the three worlds. Thus when the demigods had almost finished drinking the nectar, the Lord, in the presence of all the demons, disclosed His original form.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
पीतप्रायेऽमृते देवैर्भगवान् लोकभावनः । पश्यतामसुरेन्द्राणां स्वं रूपं जगृहे हरिः
pītaprāye'mṛte devairbhagavān lokabhāvanaḥ | paśyatāmasurendrāṇāṃ svaṃ rūpaṃ jagṛhe hariḥ
SB 8.9.27